Synchronmaschine

Abstract

The invention relates to an inductively electrically excited synchronous machine (1), comprising a machine stator (2), a machine rotor (3), and a rotary transformer (7) having a stator-fixed transformer stator (8) with a primary coil (10) and a rotor-fixed transformer rotor (9) with a secondary coil (11). The transformer stator (8) has a transformer housing (13) having a lower housing part (14) and an axially adjacent upper housing part (15), which delimit a housing interior (16) in which the transformer rotor (9) and the primary coil (10) are arranged. The assembly of the synchronous machine (1) can be simplified in the area of ​​the rotary transformer (7) if the machine stator (2) has a plurality of axial centering openings (17) distributed in the circumferential direction (U), if the lower housing part (14) has a plurality of axial through-openings (18) distributed in the circumferential direction (U), if the upper housing part (15) has a plurality of axially projecting sleeves (19) distributed in the circumferential direction (U), and if the centering openings (17), the through-openings (18) and the sleeves (19) are coordinated with one another in such a way that, in a predetermined rotational position between the machine stator (2), the lower housing part (14) and the upper housing part (15), the sleeves (19) each penetrate axially through a through-opening (18) into a centering opening (17).

Description

The present invention relates to an inductively electrically excited synchronous machine according to the preamble of claim 1.A synchronous machine of the generic type is known, for example, from DE 10 2021 212 205 A1 and comprises a machine stator, a machine rotor, a rotary transformer and a rectifier. The machine stator has a stator winding in the usual manner. The machine rotor is mounted on the machine stator such that it can rotate about an axis of rotation and has a rotor shaft with a rotor winding. The rotary transformer serves to supply the rotor winding with electrical energy and has a stator-fixed transformer stator with a primary coil and a rotor-fixed transformer rotor with a secondary coil. The rectifier is arranged fixed to the rotor and serves for the electrical coupling of the secondary coil to the rotor winding. The transformer stator has a transformer housing which has a housing lower part and a housing upper part which bears axially against it. The lower housing part and the upper housing part delimit a housing interior space in which the transformer rotor is arranged rotatably about the axis of rotation and in which the primary coil is arranged fixed to the stator.Further synchronous machines with rotary transformers are known from DE 10 2017 214 776 A1 and from U.S. Pat. No. 5,519,275 A.In the case of a multi-part transformer housing, the housing lower part and the housing upper part must be mounted precisely on one another and on the transformer stator in order to be able to achieve the highest possible efficiency for the induction effect between primary coil and secondary coil. Narrow gap dimensions are particularly advantageous here. In an axially constructed rotary transformer, an axial gap is provided between the primary coil and the secondary coil, which gap is configured as small as possible for an efficient induction effect. Since the transformer housing is arranged fixed to the stator, a corresponding radial gap must also be provided between the rotor shaft of the machine rotor and the transformer housing, wherein a small gap dimension is also sought here for a compact design. Taking these boundary conditions into account, the installation of the synchronous machine in the region of the rotary transformer is comparatively complicated.In the present context, a "configuration" is synonymous with a "configuration" and / or "device", such that the phrase "configured such that" is synonymous with the phrase "configured and / or configured such that".The present invention is concerned with the problem of specifying an improved or at least one other embodiment for a synchronous machine of this type, which is distinguished in particular by simplified mounting in the region of the rotary transformer.This problem is solved according to the invention by the subject matter of the independent claim. Advantageous embodiments are the subject of the dependent claims.The present invention is based on the general idea of configuring or matching the machine stator, the housing lower part and the housing upper part such that during mounting a predetermined rotational position between the machine stator, the housing lower part and the housing upper part and a centering of the housing lower part and the housing upper part relative to the rotational axis is automatically formed. This simplifies the assembly considerably.In particular, it is proposed for this purpose to equip the machine stator with a plurality of axial centering openings arranged distributed in the circumferential direction, to equip the lower housing part with a plurality of axial through-openings arranged distributed in the circumferential direction, and to equip the upper housing part with a plurality of axially protruding sleeves arranged distributed in the circumferential direction. Furthermore, it is proposed to adapt the centering openings, the through openings and the sleeves to one another such that, in a predetermined rotational position between the machine stator, the housing lower part and the housing upper part, the sleeves each axially penetrate through one of the through openings axially into one of the centering openings. This ensures that the upper housing part can be attached to the lower housing part only in the predetermined rotational position and that the transformer housing can be attached to the machine stator only in the predetermined rotational position. The positioning of the centering openings and the sleeves also simultaneously allows centering with respect to the axis of rotation.According to an advantageous embodiment, the centering openings, the through openings and the sleeves can be matched to one another such that the sleeves only penetrate axially through one of the through openings into one of the centering openings in a single predetermined rotational position between the machine stator, the housing lower part and the housing upper part. For example, for proper assembly for electrical connections of the transformer housing, a specific rotational position with respect to the machine stator may be required. By means of the proposed coordination of the components, this rotational position can be automatically found during the mounting of the transformer housing. In addition, this prevents mounting with an incorrect rotational position.According to an advantageous embodiment, screws can be screwed through the sleeves into the machine stator. With the aid of the screws, the transformer housing can be fixed to the machine stator in the respective rotational position in a simple and secure manner.A development is preferred in which the machine stator has within the centering openings in each case an axial screw opening which is arranged concentrically with respect to the respective centering opening. In addition, a cross section of the respective screw opening can be smaller than a cross section of the respective centering opening. This allows the respective sleeve to penetrate into the centering openings without the screw being thereby prevented from being introduced through the respective sleeve into the screw opening. The respective screw is then screwed in one such screw opening.In another advantageous refinement, it can be provided that the respective screw has a screw head which presses the upper housing part against the lower housing part and the lower housing part against the machine stator. This achieves secure fixing. The screw head can be supported directly on the upper housing part or indirectly on the upper housing part via a disk.The centering openings can expediently be configured cylindrically and can have a circular inner cross section. Expediently, the through-openings can be configured cylindrically and can have a circular inner cross section. Expediently, the sleeves can be hollow-cylindrical and can have a circular inner cross section and / or a circular outer cross section.In another advantageous embodiment, the machine stator can have an axial depression concentrically with the centering openings, into which depression the housing lower part is inserted axially. This realizes an axially compact arrangement of the transformer housing in the synchronous machine.An embodiment is advantageous in which the housing lower part has a flange on which the through-openings are formed. The flange of the housing bottom portion simplifies the use of screws for fixing the transformer housing to the machine stator. Such a flange requires little installation space in the axial direction, as a result of which an axially compact construction can be realized in a simple manner.According to an advantageous embodiment, the housing lower part can have a pot-shaped housing body which has a housing base and a circumferential housing wall. The flange of the housing lower part can be formed on the housing wall at an end of the housing wall remote from the housing bottom. Furthermore, the depression and the housing lower part can be matched to one another in such a way that an axial gap is formed axially between the housing base and the machine stator within the depression and a radially encircling radial gap is formed radially between the housing wall and the machine stator. By means of the axial gap and the radial gap, a substantial decoupling of the transformer housing from the machine stator can be achieved. This makes it possible, for example, to reduce the transmission of vibrations of the machine stator to the transformer housing.According to another embodiment, the upper housing part can have a flange on which the sleeves are formed. Here too, the use of a flange can support an axially compact design for the synchronous machine in the region of the rotary transformer. The flange of the upper housing part also simplifies the use of screws for fixing the transformer housing to the machine stator. Additionally or alternatively, the upper housing part can have a pot-shaped housing body which has a housing base and a circumferential housing wall. In this case, it can be provided in particular that the flange of the upper housing part is formed on the housing wall at an end of the housing wall remote from the housing bottom. In this way, in particular, the volume of the housing interior can be increased.According to an advantageous embodiment, the sleeves can be formed integrally on the upper housing part. This results in simple production for the upper housing part with the sleeves formed thereon. For example, the upper housing part can be made of plastic as an injection-molded part. Additionally or alternatively, the housing lower part can be produced from plastic as an injection-molded part.According to an advantageous embodiment, it is possible to use an additional embodiment. An inner cross section of the respective through-opening and an outer cross section of the respective sleeve have the same nominal diameter. Additionally or alternatively, an inner cross section of the respective centering opening and an outer cross section of the respective sleeve can have the same nominal diameter. By using the same inner diameter for the outer cross section of the sleeves and the inner cross section of the through openings on the one hand and / or the inner cross section of the centering openings on the other hand, the desired rotational position between the housing parts on the one hand and between the transformer housing and the machine stator on the other hand can be realized with high accuracy.It is clear that here the same nominal diameters can be produced only within the scope of the usual tolerances, so that the actual diameters or cross sections can vary within the scope of the tolerances. For the tolerances provided here, for example, a relatively tight clearance fit or a relatively tight transition fit are possible.In order to be able to introduce the sleeve axially into the through-opening and then into the centering opening better, the through-opening can have a chamfer at its free end preceding during the introduction.In an advantageous embodiment, it can be provided that a ferrite core is arranged in a stator-fixed manner in the transformer housing, said ferrite core surrounding the primary coil and the secondary coil. With the aid of the ferrite core, the efficiency of the inductive interaction between primary coil and secondary coil can be significantly improved.Expediently, the ferrite core can be divided axially and have an upper core part arranged in the upper housing part and a lower core part arranged in the lower housing part. Due to the axial division of the ferrite core, the primary coil and the secondary coil can be arranged axially within the ferrite core in a simple manner.Expediently, the rotor shaft of the machine rotor can penetrate concentrically into the transformer housing and carry the transformer rotor in the interior of the transformer housing. A complete axial penetration of the transformer housing from the rotor shaft is not necessary here, but should not be excluded.Expediently, the transformer rotor can have a coil carrier which is fastened to the rotor shaft of the machine rotor and to which the secondary coil is fastened and / or formed. With the aid of such a coil carrier, an axial construction for the rotary transformer can be realized in particular, in which the primary coil and the secondary coil are separated from one another via an axial gap.Further important features and advantages of the invention are evident from the dependent claims, from the drawings and from the associated description of the figures with reference to the drawings.It is understood that the features mentioned above and those still to be explained below can be used not only in the respectively specified combination, but also in other combinations or alone, without departing from the scope of the invention as defined by the claims. The above-mentioned components of a superordinate unit, such as a device, a device or an arrangement, which are designated separately, can form separate components or components of this unit or can be integral regions or sections of this unit, even if this is illustrated differently in the drawings.Preferred exemplary embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally the same components.They show, in each case schematically, FIG. 1 is an isometric view of a synchronous machine in the region of a partially cut rotary transformer, FIG. 2 shows a longitudinal section of the synchronous machine in the region of the rotary transformer, FIG. 3 is an isometric view in the region of a sleeve of an upper housing part.According to FIG. 1, an inductively electrically excited synchronous machine 1 comprises a machine stator 2 which usually has a stator winding not shown here. The synchronous machine 1 also has a machine rotor 3 which is mounted on the machine stator 2 such that it can rotate about a rotational axis 4 and which has a rotor shaft 5 and a rotor winding 6. The axis of rotation 4 defines an axial direction X which runs parallel to the axis of rotation 4 and a circumferential direction U which runs around the axis of rotation 4. The radial direction is perpendicular to the axis of rotation 4.The synchronous machine 1 also has a rotary transformer 7 which serves to supply the rotor winding 6 with electrical energy. Rotary transformer 7 comprises a stator-fixed transformer stator 8 and a rotor-fixed transformer rotor 9. The synchronous machine 1 is also equipped with a rectifier 12 fixed to the rotor, via which the secondary coil 11 is electrically coupled to the rotor winding 6. In the example of FIG. 1, the rectifier 12 is formed on the transformer rotor 9. Alternatively, the dish director 12 can also be arranged, for example, on an axial end face of a rotor lamination pack 48.The transformer stator 8 has a transformer housing 13 which has a housing lower part 14 and a housing upper part 15 which bears axially against the housing lower part 14. The lower housing part 14 and the upper housing part 15 delimit a housing interior 16 in which the transformer rotor 9 with the secondary coil 11 is arranged such that it can rotate about the axis of rotation 4 and in which the primary coil 10 is arranged such that it is fixed to the stator. The rotary transformer 7 has an axial structure such that the primary coil 10 and the secondary coil 11 are axially adjacent and separated from each other by an axial gap 49.According to FIG. 2, the machine stator 2 comprises a plurality of axial centering openings 17 which are arranged distributed in the circumferential direction U, of which, however, only one can be seen in FIG. 2. The housing lower part 14 has a plurality of axial through-openings 18 which are arranged distributed in the circumferential direction U, of which, however, only one can be seen in FIG. 2. The upper housing part 15 has a plurality of axially protruding sleeves 19 which are arranged distributed in the circumferential direction U, of which, however, only one can be seen in FIG. 2. The same number of centering openings 17 as the through openings 18 and sleeves 19 are expediently provided. The centering openings 17, the through openings 18 and the sleeves 19 are matched or configured to one another such that, in a predetermined rotational position between the machine stator 2, the housing lower part 14 and the housing upper part 15 as shown in FIG. 2, the sleeves 19 each axially penetrate through one of the through openings 18 into one of the centering openings 17. In an advantageous embodiment, it can even be provided that the centering openings 17, the through openings 18 and the sleeves 19 are matched to one another such that the sleeves 19 can only axially penetrate into one of the centering openings 17 in a single predetermined rotational position between the machine stator 2, the lower housing part 14 and the upper housing part 15.According to FIG. 2, a screw 20 is also provided for each sleeve 19, which is screwed through the respective sleeve 19 into the machine stator 2, of which only one can be seen in FIG. 2. Expediently, the machine stator 2 can have within the respective centering opening 17 in each case an axial screw opening 21, which is arranged concentrically with respect to the respective centering opening 17, of which, however, only one can be seen in FIG. 2. The respective screw 20 is screwed into such a screw opening 21. For this purpose, a screw shank 22 has an external thread 23 which is formed in a complementary manner to an internal thread 24 which has the screw opening 21. The screw 20 can also have a screw head 25 which, in the example of FIG. 2, is supported directly on the upper housing part 15. In the screwed-in state, the screw head 25 presses the upper housing part 15 against the lower housing part 14 and the lower housing part 14 against the machine stator 2.In the example of FIG. 2, the machine stator 2 has, concentrically with the centering openings 17, an axial depression 26 which the housing lower part 14 is inserted axially. The housing lower part 14 can have a flange 27 radially on the outside, on which the through-openings 18 are formed. The housing lower part 14 can furthermore have a pot-shaped housing body 28, which has a housing base 29 and a circumferential housing wall 30. The flange 27 of the lower housing part 14 is formed at an end of the housing wall 30 remote from the housing base 29. An axial gap 31 is formed within the depression 26 axially between the housing base 29 and the machine stator 2. Furthermore, a radially encircling radial gap 32 is formed within the depression 26 radially between the housing wall 30 and the machine stator 2.In the example shown here, the upper housing part 15 also has a flange 33 radially on the outside, on which the sleeves 19 are formed. Furthermore, the upper housing part 15 also has in the example a pot-shaped housing body 34, which has a housing base 35 and a circumferential housing wall 36, wherein the flange 33 of the upper housing part 15 is formed at an end of the housing wall 36 remote from the housing base 35.The flange 27 of the lower housing part 14 and / or the flange 33 of the upper housing part 15 can be formed so as to be circumferential in the circumferential direction U. An embodiment shown in FIG. 3 is likewise possible, in which the flange 33 of the upper housing part 15 is segmented in the circumferential direction U and is formed only along a plurality of circumferential sections, namely only where a sleeve 19 is provided. In a corresponding manner, the flange 27 of the housing lower part 14 can now also be segmented and can only be formed along those circumferential sections in which a through-opening 18 is provided.The respective sleeve 19 contains a sleeve through-opening 37, which axially penetrates the sleeve 19 and the upper housing part 15 in the region of the sleeve 19. The screw 20 is inserted with its shank 22 through the sleeve through-opening 37.The lower housing part 14 and the upper housing part 15 can be manufactured from plastic as injection molded parts. In particular, the sleeves 19 can be integrally and materially unitarily formed on the upper housing part 15.In the preferred example shown here, the centering openings 17 are of cylindrical configuration and have a circular inner cross section 40. The through-openings 18 are cylindrical and have a circular internal cross section 38. The sleeves 19 are hollow-cylindrical and have a circular inner cross section, which forms the likewise cylindrical sleeve passage opening 37, and a circular outer cross section 39.For a particularly good positioning between the upper housing part 15 and the lower housing part 14 on one another, the inner cross section 38 of the respective passage opening 18 can have the same nominal diameter as the outer cross section 39 of the respective sleeve 19. For an optimum positioning of the transformer housing 13 on the machine stator 2, the inner cross section 40 of the respective centering opening 17 can also have the same nominal diameter as the outer cross section 39 of the respective sleeve 19.A ferrite core 42 can be fixedly arranged in the transformer housing 13 in a stator, which ferrite core is configured such that it surrounds the primary coil 10 and the secondary coil 11. For this purpose, the ferrite core 42 can be divided axially in such a way that it has an upper core part 43 arranged in the upper housing part 15 and a lower core part 44 arranged in the lower housing part 14. According to FIG. 2, the upper core part 43 can be glued into the upper housing part 15. Likewise, the core lower part 44 can be glued into the housing lower part 14. A corresponding bond is designated here as 45. The bonding 45 can be effected with a synthetic resin.According to FIG. 1, the rotor shaft 5 can penetrate concentrically into the transformer housing 13 and carry the transformer rotor 9 in the interior of the transformer housing 13, namely in the housing interior 16. The transformer rotor 9 can have a coil carrier 46, which is attached to the rotor shaft 5 in a rotationally fixed and axially fixed manner and to which the secondary coil 11 is fastened or formed.In the example of FIG. 1, the rectifier 12 is also arranged or formed on the coil carrier 46.In FIG. 1, a bearing 47 for rotatably supporting the rotor shaft 5 on the machine stator 2 is also indicated.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2021 212 205 A1

[0002] DE 10 2017 214 776 A1

[0003] U.S. Pat. No. 5,519,275 A

[0003]

Claims

Inductively electrically excited synchronous machine (1), - having a machine stator (2), - having a machine rotor (3) which is mounted on the machine stator (2) such that it can rotate about a rotational axis (4) and which has a rotor winding (6), - having a rotary transformer (7) for supplying the rotor winding (6) with electrical energy, which transformer has a transformer stator (8) fixed to the stator and a transformer rotor (9) fixed to the rotor and having a secondary coil (11), - having a rectifier (12) fixed to the rotor, via which the secondary coil (11) is electrically coupled to the rotor winding (6), - wherein the transformer stator (8) has a transformer housing (13) which has a housing lower part (14) and a housing upper part (15) which bears axially against it, - wherein the housing lower part (14) and the housing upper part (15) delimit a housing interior (16), in which the transformer rotor (9) is arranged rotatably about the axis of rotation (4) and in which the primary coil (10) is arranged fixedly on the stator, characterized - in that the machine stator (2) has a plurality of axial centring openings (17) distributed in the circumferential direction (U), - in that the housing lower part (14) has a plurality of axial through-openings (18) distributed in the circumferential direction (U), - in that the housing upper part (15) has a plurality of axially protruding sleeves (19) distributed in the circumferential direction (U), - in that the centring openings (17), the through-openings (18) and the sleeves (19) are matched to one another such that, in a predetermined rotational position between the machine stator (2), the housing lower part (14) and the housing upper part (15), the sleeves (19) each axially penetrate through a through-opening (18) axially into a centring opening (17).Synchronous machine (1) according to Claim 1, characterized - in that the centring openings (17), the through openings (18) and the sleeves (19) are matched to one another in such a way that the sleeves (19) enter axially into a centring opening (17) in each case only in a single predetermined rotational position between the machine stator (2), the housing lower part (14) and the housing upper part (15).Synchronous machine (1) according to Claim 1 or 2, characterized - in that screws (20) are screwed through the sleeves (19) into the machine stator (2).Synchronous machine (1) according to Claim 3, characterized - in that the machine stator (2) has within the centring openings (17) in each case an axial screw opening (21) which is arranged concentrically with respect to the respective centring opening (17), - in that the screws (20) are in each case screwed into such a screw opening (21).Synchronous machine (1) according to Claim 3 or 4, characterized - in that the respective screw (20) has a screw head (25) which presses the upper housing part (15) against the lower housing part (14) and the lower housing part (14) against the machine stator (2).Synchronous machine (1) according to one of the preceding claims, characterized - in that the machine stator (2) has, concentrically with respect to the centring openings (17), an axial depression (26), into which the housing lower part (14) is inserted axially.Synchronous machine (1) according to one of the preceding claims, characterized - in that the housing lower part (14) has a flange (27) on which the through-openings (18) are formed.Synchronous machine (1) according to Claims 6 and 7, characterized - in that the housing lower part (14) has a pot-shaped housing body (28) which has a housing base (29) and a circumferential housing wall (30), - in that the flange (27) of the housing lower part (14) is formed on the housing wall (30) at an end remote from the housing base (29), - in that the depression (26) and the housing lower part (14) are matched to one another such that an axial gap (31) is formed axially between the housing base (29) and the machine stator (2) within the depression (26), and an annularly circumferential radial gap (32) is formed radially between the housing wall (30) and the machine stator (2).Synchronous machine (1) according to one of the preceding claims, characterized - in that the upper housing part (15) has a flange (33) on which the sleeves (19) are formed, and / or - in that the upper housing part (15) has a pot-shaped housing body (34) which has a housing base (35) and a circumferential housing wall (36), wherein the flange (33) of the upper housing part (15) can be formed on the housing wall (36) at an end remote from the housing base (35).Synchronous machine (1) according to one of the preceding claims, characterized - in that the sleeves (19) are formed integrally and / or in the same material on the upper housing part (15).Synchronous machine (1) according to one of the preceding claims, characterized - in that an inner cross section (38) of the respective through-opening (18) and an outer cross section (39) of the respective sleeve (19) have the same nominal diameter, and / or - in that an inner cross section (40) of the respective centring opening (17) and an outer cross section (39) of the respective sleeve (19) have the same nominal diameter.Synchronous machine (1) according to one of the preceding claims, characterized - in that a ferrite core (42) is arranged in a stator-fixed manner in the transformer housing (13), said ferrite core surrounding the primary coil (10) and the secondary coil (11).Synchronous machine (1) according to Claim 12, characterized - in that the ferrite core (42) is divided and has an upper core part (43) arranged in the upper housing part (15) and a lower core part (44) arranged in the lower housing part (14).Synchronous machine (1) according to one of the preceding claims, characterized - in that a rotor shaft (5) of the machine rotor (3) penetrates concentrically into the transformer housing (13) and carries the transformer rotor (9) in the interior of the transformer housing (13).Synchronous machine (1) according to one of the preceding claims, characterized - in that the transformer rotor (9) has a coil carrier (46) which is fastened to a rotor shaft (5) of the machine rotor (3) and to which the secondary coil (11) is fastened and / or formed.

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